Rock drill



July 21, 1936. C HUFFMAN 2,047,965

ROCK DRILL Filed March 6, 1934 3 Sheets-Sheet l [YR] WIN flew/animagwmzm 6.

A; A Mm- July 21, 1936. M. c. HUFFMAN ROCK DRILL 3 Sheets-Sheet 3 Filed March 6, 1934 e/ZZZy Patented July 21, 1936 UNHTED STATES PATENT OFFICE ROCK DRILL Application March 6, 1934, Serial No. 714,312

15 Claims.

This invention relates to rock drilling mechanisms, and more particularly to improvements in the feeding and guiding means for a rock drill of the mounted hammer type.

An object of this invention is to provide an improved rock drilling mechanism. Another object is to provide an improved feeding means for a rock drill of the mounted, self-feeding, hammer type. A further object is to provide an improved supporting and guiding structure for a rock drill. Yet another object is to provide an improved pneumatic feeding means for a rock drill and having improved feed controlling means for regulating the feeding pressure. Another object is to provide an improved pneumatic feeding means for a rock drill whereby a feed of comparatively great length is obtained by means of a relatively compact structure and having improved transmission connections between the power feeding piston' and the drill whereby such compactness is possible, and improved fluid sealing means associated with said transmission connections whereby fluid leakage from the feeding cylinder is reduced to a minimum; the improved sealing means cooperating with elements of the drill guiding means. Still another object is to provide improved flexible, force transmitting means between the power feeding element and the drill, and with which the improved fluid sealing means is associated, whereby leakage of fluid from the feed cylinder past the flexible means is substantially eliminated. A further object is to provide an improved tower mounted rock drilling mechanism, supported by a wheeled carriage and having improved drill supporting and guiding means and improved means for feeding the drill. These and other objects and advantages of the invention will, however, hereinafter more fully appear.

In the accompanying drawings there is shown, for purposes of illustration, one form which the invention may assume in practice.

In these drawings,--

Fig. 1 is a front elevational View of the illustrative embodiment of the improved rock drilling mechanism.

Fig. 2 is a side elevational view of the drilling mechanism shown in Fig. 1.

Fig. 3 is a cross sectional view taken on line 3-3 of Fig. 2.

Fig. 4 is a cross sectional view taken on line 5- 5 of Fig. 2.

Fig. 5 is a detail sectional View taken on line 5-5 of Fig. 2.

Fig. 6 is a central, longitudinally extending,

vertical sectional view taken through the improved drill feeding and guiding structure.

Fig. 7 is a longitudinally extending, vertical sectional view taken substantially on line 1-1 of Fig. 6.

Fig. 8 is a detail sectional view with parts in elevation, showing the improved feed control means.

Fig. 9 is a horizontal line 9--9 of Fig. 8.

Figs. 10, 11, 12 and 13 are detail sectional views taken on lines,lU--|0, H-l|, l2-l2, and l3|3, respectively, .of Fig. 8.

As shown in the drawings, the improved rock drilling mechanism is of the tower mounted, self- 15 feeding type, particularly designed for use in quarry work, although it will be evident that the improved structure constituting the features of this invention may be incorporated in drills of various other types.

The drilling mechanism disclosed herein comprises a wheeled carriage I having a tower support and guide, herein in the form of a standard 2, mounted thereon, and on which a rock drill 3 is supported and. guided in an improved manner. The wheeled carriage l comprises a frame 4, herein generally triangular in shape, supported on an axle 5 for the carriage wheels 6 and hav ing an adjustable ground engaging supporting leg I and a suitable draft connection 8 whereby the entire drilling unit may be towed to different locations.

Supported on the carriage frame 4 and superimposed on the wheel axle is a horizontal plate 9 having spaced parallel bores l0, ID for receiving the lower portions of parallel vertically arranged guide members II, II of tubular form. The upper portions of these parallel tubular members are similarly received within spaced parallel bores l2, l2 formed in a top plate I 3. These tubular members are, as disclosed herein, secured within the bores in the plates 9 and I 3 by releasable set screws threaded within the plates and engaging the tubular members. Arranged parallel with the tubular members II, II, with its axis lying in a vertical plane midway between the tubular members but oflset rearwardly therefrom, is a vertically arranged tubular member I4, herein the feeding cylinder of the pneumatic drill feeding means, this feeding cylinder extending coextensively with the members II and secured, as by welding or otherwise, to brackets formed integral with the plates 9 and I 3. The elements II and I4 may be suitably braced with respect to the wheeled carriage, as by suitable brace rods exsectional view taken on 10 ing or standard on which the rock drill is supported and guided. 7

The rock drill 3 is herein of the pressure fluid actuated, hammer type of a standard design, and is detachably mounted on a supporting and guiding frame t5, the latter having formed along :its lateral edges concave guiding surfaces l6, l6 slidingly engaging with'the inner curved sides of the I,

exterior surfaces of the parallel tubular members H, H. The rock drill is detachably secured to the frame l5 by means of a transyerse holding bolt l! passing through an opening formed the back head of the drill, and by'clar'n-p'ing bolts I8, I 8 engaging with the usual drill side rods, the drill being readily detachable from the guiding frame l5 upon release of the holding elements I! and I8. valve ,member l9 operated Joya handle .20. 7 V Arranged withinthe cylinder 2| of the rock drill is a usual hammer rpi-ston,.not shown, actuated by pressure fluid, for'percussively actuating a usual rock drill steel 22 supported in=a usual mannerwithin the front chuck housing 23 of the drill, there being ,providedsuitable steel retainer means 24 formaintaining the drill steel in operative position within the drill chuck. Forguiding the drill steel 22 during starting of ahole, there is provided a steel centralizer comprisingcooperatingguide members 25, '25 supported .on .the bottom plate 9 and pivotally mounted onthe lower portions of the tubular members ll, I I j and these members, when ,swung inwardly into their steel guiding position .with the guiding portions 26 thereof embracing the drill .steel, are held in such relation by means of a U-shaped holding element 21 engaging the outer sides of the members 25 in the manner shown in Fig. 5. Theguidingelements of the centralizer may be readily released simply by withdrawing'lthe element 2;! from its holding position and swinging the guiding elements 25 laterally out of guiding relation with the drill steel. r v I Now referring to the improved feeding :mech: anism, and .more particularlyv to the improved flexible transmission connections and their associated fluid sealing means, .it will ,be ,observedthat containedin the feeding cylinder M .and reciprocable longitudinally in either directionrelative thereto under the action of pressure fluid, is a feeding. piston 2.8, while reciprocably mounted within the bores of the tubular members .l,are sealing elements, .herein in ;the.form of pistons 1 29 and 39.. The feed piston 28 comprises a body element J3l having a central flange against-which there are secured, as "by, clamping elements .32, suitable cuppackings33, the elements 32 .being held in position on "the piston body by 'means of holding nuts 35 threaded on the'opposite'sidesof the body element. Threadedly secured'within'the oppositeends of the body element 3l of the piston areadjustable eye-bolt members 35 connected to the. adjacent ends of [flexible transmission-elements 36 and '31, each in the formof aroller chain of the block type. As shownin Fig. 6, "these 'rolle-r chain sectionsare connected to the opposite sides of thefeed piston,'and the other ends of these chains are adjustably -connectedat 38=each to a body. element 39 of. the seal pist0ns29and 38.

As shown .in Figs. 6 and '7, the t ppenerrdpf one of the tubular members it and .thelower. end of the other tubular member are :reversely bent, at 4i) and M,- respectively, in v U shaped:forrnj The rock drill has a usual throttle and the reversely bent portions of these members 7 each project within a bore 42 formed in a head 43 of the feed cylinder, and each is held in sealed 7 relation therein by means of a packing 44 held' under compression in engagement with the exterior periphery of the tubular member by an adjustable plug 45 threaded within'the cylinder head. The chain sections 36 and 3'! extend in opposite directions upwardly and downwardly through'the ends of the feed cylinder, and the upper chain section 36 is guided by the rollers thereof on the inner curved surface 46 of the upper bent portion 40 of the tubular member! I,

and extends through the tubular member H into connection with'the sealing piston 30, while the lower chain section 37 extends in a similar man-- ner about the bottom bent portion 4l'of theother tubular member I I and through this member into connection, at 38, with the other sealing piston 29. Each of the sealing pistons 29 and 30 comprises'a head ll'l formed on the body element 39, andrthe piston body element has 'threadedly secured thereto an adjustable member. :48 be tween which and the head 41 there iscompressed suitable packing material 59. Adjustably threadedly engaged at 159 within the top of the seal ing piston 29 is a member 5| secured to the ad-v jacent endo'f a flexible transmission element 52, herein the form of :a cable or wire rope and thislfiexible element eXten-d's iupwardly through the tubular member-A l :and out through the open top ofithis ftubular'memloer; in :the manner shown in Fig.6, theacable passing around a pulley 53 journaled on'a shaft 54 carried byabrack 'et .55 securedto' the top plate '13. This cable passes" from this pulley 53 and extends downwardly midway between the tubular members H; in a direction parallel therewith, and is secured in a suitable manner to .an adjustable member 56' in turn secured by a nut at 51 within'the rear portion of the Igui'de frame 1-5 of the drill. Adjustably threadedly secured within the'bottom of the other sealing piston 3-53 is a member 58 having secured theretothe adjacent end of awire rope orcable '59, similar to the =cable52 and extending in a similar manner downwardly through the tubular member l1 and out through the open lower end of the latter andaround a guide pulley 68 journaled :on a shaft 6 carried by a bracket 62 securedfto the bottom plate 9. This cable extend-s from the pulley '60 upwardly midway between the members ll, '1 l, in adirection parallel therewith, and is secured within a threaded member 153 adjustably secured by a nut, as at 64, within the forward portion of the drill guidingframe [5. The adjusting members 5B and a 63 are secured to the ends of the wire tropes by within which the sealing piston 3lli'is reciprocably mounted; while .the tubular members, at the other sides of the sealing pistons, open out directly to atmosphera and these sealing pistons prevent substantial leakage of fluid from the opposite ends of the feed cylinder, through the tubular members, past the sealing pistons r Now referring to the improvedmeans for controlling the flow of pressure fluid to the feeding means to regulate the feeding pressure, it will be noted that secured in a suitable manner, as by welding, to the rear side of the feed cylinder isavalve box 66 having a conical valve bore 51 in which is rotatably mounted a controlling valve 68of conical shape. Formed on the valve is a shank 69 having secured thereto a handle 19. Secured within thevalve box is an air inlet pipe H which leads to any suitable source of pressure fluid supply; and pressure fluid is conducted from this pipe'through a passage 12 communicating with the internal Valve chamber at the inner end of the. valve. The valve is made hollow at 13, and communicating with the hollow, portion 13 is an axial bore 14 extending through the valve shank. The walls of the valve are perforated byalined ports 15 communicating with the hollow interior 13 of the valve for connecting a. pas sage'lfi with the pressure fluid supply; and this passage is connected, by a connection Tl secured within the valve box, to a flexible hose connection 18, through which pressure fluid is supplied to theinlet connection 19 of the throttle valve I!) of the rock drill 3. Formed in different transverse planes on the exterior periphery of the valve are circumferentially extending grooves 89, 8|, 82 and 83, the grooves 89 and 8| communicating through the bore with the fluid supply, through passages 84 and 85. Formed in the valve box and communicating with the valve bore are passages 86 and 81; and these passages are connected'by suitable conduits, such as pipe connections 88 and 89'respectively, to the upper and lower ends of the feed cylinder, the passage 86 constituting a forward feed passage and the pas sage 81 constituting areverse feed passage. Also formed in the valve box for connecting the valve bore to atmosphere, are vent passages 98 and 9!. For controlling the flow of pressure fluid from the hollow interior T3 of the valve to the axial bore 14, there'is reciprocably mounted in the bore 14 a plunger valve 92 having a suitable operating pushbutton 93 mounted within the valve handle 19, and this plunger valve has formed on its inner face a valve portion 94 adapted to seat on a valve seat 95. When the valve 92 is pushed inwardly to bring the same into seated position on the seat 95, flow of pressure fluid through the bore 14 to the forward and reverse feed passages is cut off, and by varying the po sition of the valve the flow of feeding pressure fluid may be correspondingly varied. The valve and push button are normally held in their released position by the pressure fluid acting on the inner end of the valve.

- Means is provided, associated with the control valve mechanism, for automatically regulating the feeding pressure, and this automatic means comprises a ball valve 9'! held on its seat 98, in a position closing the passage 86, by a coiled spring 99. The tension of the spring 99 is adjustable by a follower member I09 threaded within a bushing Hll, in turn threadedly engaged within the valve box; and this follower member H30 is provided with a suitable operating handle I82. Byregulating the tension of the spring 99, the flow of pressure fluid to the forward feed passage may be regulated as desired, so that any desired forward feeding pressure within the feed cylinder may be attained.

The operation of the improved drilling mechanism will be clearly apparent from the description given. When the control valve 68 is rotated into 7 a position to bring the groove into communication with the forward feed passage 86, pressure fluid may flow through the valve, through the passage 86, past the automatic regulating valve 91, and through the pipe connection 88 to the upper end of the feed cylinder, the pressure fluid flowing to the upper end of the feed cylinder acting on the upper face of the feed piston to effect movement of the latter downwardly within the feed cylinder. Downward movement of the feed piston is transmitted through the chain section 36 and the cable section 59 to the guide frame of the rock drill, so that as the feed piston moves downwardly within its cylinder the rock drill moves in the same direction forwardly along its guides. When the control valve is in this position, the lower end of the feed cylinder at the lower side of the feed piston is vented to atmosphere through the passage 81, groove 82 and vent passage 96. The supply of feeding pressure to effect forward feed may be regulated as desired 11 by regulating the tension of the spring 99 of the automatic regulating valve. Forward feed may be manually regulated simply by controlling the position of the plunger valve 92 to regulate the flow of pressure fluid through the passage 85. Reverse feed may be effected by rotating the control valve 68 to a position wherein the groove 83 communicates with the reverse feed passage 31, and pressure fluid then flows through the passage 85,

groove 8|, passage 81 and pipe connection 89,

to the lower end of the feed cylinder, the pressure fluid flowing to the lower end of the feed cylinder acting on the lower face of the feed piston to effect movement of the latter upwardly within the cylinder. This upward movement of the feed piston is transmitted to the rock drill through the lower chain section 31 and the cable section 52 connected to the rock drill guide, to move the latter rearwardly along its guides. During rear- Ward movement of the feed piston, the upper end of the feed cylinder is connected to exhaust through the groove 83 and vent passage 9!, the venting fluid by-passing around the automatic control valve 91. The reverse feeding movement of the piston may be controlled by adjusting the position of the plunger valve 92 to regulate the flow of pressure fluid through the passage 85. Of course as the feed piston reciprocates in the feed cylinder the sealing pistons reciprocates with the sealing cylinders formed by the tubular guide members, the sealing pistons moving in a direction opposite from the direction of movement of the feed piston, so that the flexible elements are at all times maintained sealed with respect to the feed cylinder.

As a result of this invention it will be noted that an improved rock drill feeding mechanism is provided, wherein a relatively long feed is attained without materially increasing the over-all dimensions of the feeding and guiding structure. It will further be noted that an improved rock drill feeding mechanism of the pneumatic type is provided, having improved flexible transmission means between the power feeding element and the rock drill, and improved sealing means associated with the transmission means whereby fluid leakage is reduced to a minimum. It will still further be evident that by the provision of the improved feeding structure, the rock drill is supported and guided in an improved manner, and that by associating the feeding elements with the guiding structure the feeding means is rendered extremely simple in design, and by its simplicity results in a feeding structure which is more rugged in design and inexpensive to manufacture. These and other uses and advantages of the improved drilling mechanismwill be clearly apparent to those skilled in the art.

While there is in this application specifically described one form which the invention may assume in practice, it will be understood that this form is shown for purposes of illustration only, and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims. r

What I claim as new and desire to secure by Letters Patent is:

1. In a rock drilling mechanism, a feed cylinder, a feed'piston reciprocable therein, tubular guide members communicatingrespectively with the opposite. ends of said feed cylinder, a rock drill guided on said members, sealing pistons reciprocable in said tubular members, flexible trans mission elements connecting saidfeed piston to said sealing pistons, and flexible transmission ele' ments connecting said' sealing pistons with the rock drill.

I 2. In a rock drilling mechanism, a feed cylintubular members, flexible transmission means connecting said feed piston to said sealing pistons, and flexible transmission means connecting said 7 sealing pistons to the rock drill.

3. In a rock drilling mechanism, parallel tubu-. lar elements, a feed cylinder parallel with said elements, one of said tubular elements having a reversely bent portion communicating with one end of the feed cylinder and the other element having a reversely bent portion communicating with the opposite end of said feed cylinder, a feed piston reciprocable in said feed cylinder, a rock drill guided for movement longitudinally of said tubular elements, flexible transmission means connected to the opposite ends of said feed piston and extending through the opposite ends of said feed cylinder and said tubular elements into connection with said rock drill, and sealing means carried by said flexible means and engaging with a sealing action the inner walls of the tubular elements for preventing leakage of pressure fluid from the opposite ends of said feed cylinder through said tubular elements.

4. In a rock drilling mechanism, parallel tubular members, arock drill guided on said tubular members for movement. longitudinally thereof, a feed cylinder parallel with said tubular members, one of said tubular members having areversely bent portion communicating with one end of said feed cylinder and the other tubular member having a reversely bent portion communicating with the opposite end of said feed cylinder, a feed piston reciprocable in said ,feed cylinder, sealing pistons reciprocable Within said tubular .members, flexible elements connected to the opposite sides of said feed piston and extending outwardly through the ends of said feed cylinder and said tubular members into connection with said sealing pistons, and flexible elements connected to said sealing pistons and extending into connection with said rock drill.

15. In a rock drilling mechanism, parallel tubular members, a rockgdrill guided on :said tubular members for movement longitudinally thereof, a

feed cylinder parallel with saidtubular members,

ton reciprocable in said feed cylinder, sealing pisflexible elements connected .to the oppositesides of said feed piston and extending outwardly tons reciprocable within said tubular members,

through the ends of said feed cylinderand said tubular members into connection with said sealing pistons, flexible elements connected to said 15' sealing pistons and extending into connection with said rock drill, and guiding means mounted at the opposite ends of said tubular members for guiding said last mentioned flexibleelements said latter flexible elements extending outwardly through said tubular members and around said guiding means and then inwardly toward one another into connection with said rock drill.

6. In a rock drilling mechanism,a feedcylinder, tubular cylinders communicating with the opposite ends of said feed cylinder, a feedpiston reciprocable in said feed cylinder, sealing piston means reciprocable in said tubular cylinder respectively, flexible connections for connectingthe opposite sides of said feed piston to said sealing piston means, a rock drill guided'on certain of said cylinders for movement longitudinally thereof, and flexible means for connecting said sealing piston means with said rock drill. v v

'7. In a rock drilling mechanism, parallel tubu lar guiding elements, a feed cylinderparallel with said elements, one of said tubular 'elements'having a reversely bent portion communicating one end of the feed cylinder and theether tubular element having a reversely bent portion communicating with the opposite end of said feed cylinder, a rock drill guided on said tubular guid ing elements for movement therealong, a'feed piston reciprocable in said feed cylinder, sealing pistons reciprocable in said tubular elements, and flexible transmission means connected to the opposite ends of said feed piston and to said sealing pistons and extending through the opposite ends of saidfeed cylinder and said tubular elementsv into connectionwith said rock drill.

8. In a rock drilling mechanism, drillguiding means including a tubular drill guide member, a feed cylinder parallel with said guide member, a feed piston reciprocable in said feed cylinder, -a rock drill guided on said guiding means, a sealing piston reciprocable in said tubular guide member, and flexible transmission elements respectively connecting said feed piston to said drill and said sealing piston to said feed piston.

, 9. In a rock drilling mechanism, a rock drill 60 and a supporting, guiding and'feeding structure for said rock drill embodying parallel tubular members, and a feed cylinder parallel with-said tubular members, said tubular members oom-V municating respectively with the opposite ends of said feed cylinder, a feed piston reciprocable in said feed cylinder, sealing pistons reciprocable in said tubular members, and means connecting said feed piston, said drill, and said sealing pistons.

10. In a rock drilling mechanism, a rock drill and a supporting, guiding and feeding structure on which saidrock drill is guided for feeding movement and embodying a feed cylinder, and a tubular sealing cylinder communicating with said feed cylinder, a feed piston reciprocable in said feed cylinder, a sealing piston reciprocable in said sealing cylinder, and flexible transmission means connecting said feed piston to said rock drill and said sealing piston to said feed piston.

11. In a rock drilling mechanism, a feed cylinder, a pair of guiding cylinders extending substantially co-extensive and parallel with said feed cylinder, one end of one guiding cylinder communicating with one end of said feed cylinder and the opposite end of said other guiding cylinder communicating with the opposite end of said 'feed cylinder, a rock drill guided on said parallel guiding cylinders for movement longitudinally therealong, a feed piston reciprocable in said feed cylinder, sealing pistons reciprocable in said guiding cylinders respectively, flexible connections Within said feeding and guiding cylinders for connecting said sealing pistons to said feed piston, and flexible connections extending within said guiding cylinders for connecting said sealing pistons to said rock drill.

12. In a rock drilling mechanism, a feed cylinder, a pair of guiding cylinders extending sub-- stantially co-extensive and parallel with said feed cylinder, one end of one guiding cylinder communicating with one end of said feed cylinder and the opposite end of said other guiding cylinder communicating with the opposite end of said feed cylinder, a rock drill guided on said parallel guiding cylinders for movement longitudinally there along, a feed piston reciprocable in said feed cylinder, sealing pistons reciprocable in said guiding cylinders respectively, flexible connections within said feeding and guiding cylinders for connecting said sealing pistons to said feed piston, flexible connections extending within said guiding cylinders for connecting said sealing pistons to said rock drill, and guiding means at the opposite ends of said cylinders for guiding said flexible connections.

13. In a rock drilling mechanism, a feed cylinder, a pair of guiding cylinders extending substantially co-extensive and parallel with said feed cylinder, one end of one guiding cylinder being reversely bent and communicating with one end of said feed cylinder and the opposite end of said other guiding cylinder being reversely bent and communicating with the opposite end of said feed cylinder, a rock drill guided on said parallel guiding cylinders for movement longitudinally therealong, a feed piston reciprocable in said feed cylinder, sealing pistons reciprocable in said guiding cylinders respectively, flexible connections within said feeding and guiding cylinders and extending around said reversely bent portions of said guiding cylinders for connecting said sealing pistons to said feed piston, and flexible connections extending within said guiding cylinders for connecting said sealing pistons to said rock drill.

14. In a rock drilling mechanism, a feed cylinder, a pair of guiding cylinders extending substantially co-extensive and parallel with said feed cylinder, one end of one guiding cylinder being reversely bent and communicating with one end of said feed cylinder and the opposite end of said other guiding cylinder being reversely bent and communicating with the opposite end of said feed cylinder, a rock drill guided on said parallel guiding cylinders for movement longitudinally therealong, a feed piston reciprocable in said feed cylinder, sealing pistons reciprocable in said guiding cylinders respectively, flexible connections within said feeding and guiding cylinders and extending around said reversely bent portions of said guiding cylinders for connecting said sealing pistons to said feed piston, and flexible connections extending within said guiding cylinders for connecting said sealing pistons to said rock drill, said reversely bent portions of said guiding cylinders providing guiding means for said first mentioned flexible connections.

15. In a rock drilling mechanism, a feed cylinder, a pair of guiding cylinders extending substantially co-extensive and parallel with said feed cylinder, one end of one guiding cylinder being reversely bent and communicating with one end of said feed cylinder and the opposite end of said other guiding cylinder being reversely bent and communicating with the opposite end of said feed cylinder, a rock drill guided on said parallel guiding cylinders for movement longitudinally therealong, a feed piston reciprocable in said feed cylinder, sealing pistons reciprocable in said guiding cylinders respectively, flexible connections within said feeding and guiding cylinders and extending around said reversely bent portions of said guiding cylinders for connecting said sealing pistons to said feed piston, flexible connections extending within said guiding cylinders for connecting said sealing pistons to said rock drill, said reversely bent portions of said guiding cylinders providing guiding means for said first mentioned flexible connections, and guiding pulleys at the opposite ends of said cylinders for guiding said second mentioned flexible connections.

MERVIN CHESTER HUFFMAN. 

